The invention relates to self-locking screw connection suitable for use with highly stressed electrical plug-type connectors for motor vehicles and the like, which serve for transmitting control signals and/or for power supply.
Standards in which important dimensions and codes for interchangeability are defined apply to plug-type connectors of this type. For example, a German standard for highly stressed two-pole to four-pole electrical connectors for road vehicles which contain round contacts and a bayonet coupling is DIN Standard 72585-1 and -2 of March, 1996. Seven-pole embodiments are also used. These connectors are intended for providing an electrical connection with components that are directly mounted on an internal combustion engine. Consequently, the connectors must be able to withstand high thermal and dynamic stresses. However, high stresses also occur when the connector is used on other fixed installations and with free-floating connectors within the line system or main system.
Primary and secondary locking elements are provided for the connector terminals in order to improve the reliability of the connector. Such secondary locking elements or retainers frequently have a complicated design and are difficult to insert.